The present invention relates to novel dialkyl quaternary fatty ammonium derivatives of natural and synthetic oils, fatty acids and/or triglycerides and to their use in personal care products.
Dialkyl quaternary fatty ammonium derivatives of relatively long chain fatty acid components are known. For example, a dibehenyl dimethyl ammonium quat has been sold under the trade name INCROQUAT DBM-90 from Croda Inc., 7 Century Drive, Parsippany, N.J. 07054. Similar ammonium based quat compounds have been described in U.S. Pat. No. 4,954,335 to Ben Janchipiaponvej. However, the ""335 patent describes such dialkyl quats as being selected from ammonium compounds having one or two long chain alkyl groups including from about 14 to about 22 carbon atoms. These compounds are said to be used as conditioning agents primarily for hair conditioners. It should be noted however that the ""335 patent, and in addition, Noe U.S. Pat. No. 4,976,956 appear to only disclose the production of conditioning agents, not shampoos or conditioning shampoos. In addition, it has been recognized that the solubility or, more correctly, the compatibility of these compounds with anionic surfactants is limited. Indeed, in the ""335 patent, even in conditioning compounds a xe2x80x9csolubilizingxe2x80x9d nonionic surfactant was necessary. While of course, such compounds could be used in shampoos, they can often have detrimental effects. They can reduce the foaming which is important to the action and feel of a shampoo, they add cost because of the need for an additional ingredient, present additional formulation obstacles and, in addition, add unnecessary surfactant to the shampoo, potentially increasing irritation. Dialkyl quats of compounds such as tallow are also known. However, these compounds are generally made from shorter chain fatty acid constituents, i.e., C-16 and C-18 fatty acids. Therefore, there remains a need for the production of conditioning agents which are compatible in shampoos which will not further complicate an already complicated formulation process.
The present invention relates to the dialkyl quats of fatty acid materials having at least about 30% of at least a C-20 fatty acid component by weight and preferably having a target melting point of about 100xc2x0 C. or less and more preferably about 85xc2x0 C. or less.
The quats in accordance with the present invention, unlike the dialkyl quats of the prior art, include an amidoamine group produced by the reaction of the carboxylic acid portion of the fatty acids with at least 2 of the nitrogens contained within a bridging molecule such as, for example, DETA. 
In the above formula I, R is the carbon chain of the fatty acid constituent and m and n are as described herein.
In addition, the dialkyl quats of the present invention are generally made from fatty acids having an iodine value of 200 or less, more preferably 150 or less and even more preferably 100 or less. The resulting quats can include, for example, compounds made exclusively from, for example, erucic acid (C22:1-22 carbon atoms with one double bond) or high erucic rapseed oil (xe2x80x9cHEAR oilxe2x80x9d). HEAR oil has a fatty acid content of 46% by weight erucic acid (C22:1), 1.5% behemic acid (C22:0), and 11% gadoleic acid (C20:1) by weight. HEAR oil has an iodine value ranging from between about 90 to about 120 depending upon grade and actual fatty acid content. Erucic acid, by comparison, has an iodine value of about 74. Erucic acid, which makes up the major portion of HEAR oil has a target melting point of about 33.5xc2x0 C.
The dialkyl quats in the present invention can also include such long chain fatty acid constituents as montan acid wax which contains, as its major constituent, a C36:0 fatty acid. Surprisingly, the compounds in accordance with the present invention have excellent anionic surfactant compatibility when compared to, for example, non-amidoamine based dialkyl quats such as those previously known. This allows them to be formulated into surfactant systems such as, for example, those present in shampoos, without the need for separate compatiblizers. Personal care products comprising a base of a shampoo, conditioner, liquid soap, facial/body wash or hair color and 0.1-10% cationic activity of the quats of the invention are also contemplated.